Moreover, this functional assay could be implemented for other IEI, but focusing on T cells to test variants in other primary immunodeficiency-related genes, with dysregulation of the PI3K-Akt-S6 pathway as previously described in some variants of CARD11 with reduced S6 phosphorylation (36), or enhanced Akt phosphorylation in double negative T cells from autoimmune lymphoproliferative syndrome (37). Here, PIK3CD is linked to inborn error of immunity.